Wood is Alive

Wood is not alive in the sense that you have to “feed it,” when it looks dry– that’s because the finish has lost it’s sheen and needs a drop of oil or wax, or a good dusting. But it’s alive in two unique ways: it’s hygroscopic, in that it takes on and releases water from its surroundings, changing size when it does. It is also anisotropic, meaning that the change in size is directional: a lot with the width, perhaps half that with the thickness, and almost not at all with the length.

These properties make working with wood a challenge at times. When changing grain direction, you have to allow for this movement our your piece will eventually self-destruct. Or not. We have at times gone to great lengths to respect this motion, making pieces most cabinetmakers consider impossible from solid wood. The Ambo at Sacred Heart Monastery comes to mind, or the Maryknoll Chair.

Here is a project that used these characteristics to make a moving, breathing sculpture. Fascinating!

I have some suspicions how they did it— my guess is, opposing grain directions on paper-thin laminations. From the sound of the article, the form was computer generated.

This is a great direction to consider when building, though the engineering would be intense for a structure in our climate. Buildings that respond to their environment just by their properties, rather than by a layer of controls and actuators. Perhaps it will happen more as we start growing our structures, rather than building them.

It reminds me of a story I heard about the value of analog systems, versus digital. A printing plant was having trouble maintaining proper humidity while working with carbon layers of multipart forms. Their equipment was not sensitive enough: sometimes the forms would swell and jam the presses, sometimes they would shrink and curl. One day the HVAC engineer came in and saw everything running perfectly. When he asked ,the plant manager said offhandedly, “yeah, I fixed that problem, it’s not bothering us any more.”

When the engineer inquired, he was shown the new humidistat: a strip of the carbon paper had been thumbtacked to the wall. A relay nearby controlled the humidifier, and the relay was controlled by wires paperclipped to the carbon and thumbtacked to the wall. When the strip of carbon paper shrank too much, the humidifier went on, when it expanded enough it went off again.